In a typical blood donation procedure, blood is collected from a donor using a plastic, disposable blood collection kit. In its most basic form, the blood collection kit includes a venipuncture needle, one or more plastic collection containers and a length of plastic tubing connected to the needle and the container(s) to provide a flow path therebetween. After collection, the blood may be further processed or stored until it is ready to be transfused to a patient.
Before it is used, however, the collected blood must be tested to establish compatibility with the patient's (recipient's) blood type (e.g. A, B, AB, O) and/or possibly for other purposes as well. Thus, samples of the donated blood must be collected for the required testing. The blood that remains in the plastic tubing after the blood donation may be used for such samples.
Recently, sealing devices have been developed to allow the plastic tubing to be sealed into one or more blood-containing segments. The segmented tubing portions can then be separated from the rest of the tube by cutting or tearing at the seal line. The blood in the detached segments can then be used for the tests that may be required. Presently, it is common to prepare up to as many as 16 separate blood-containing tubing segments which can then be used for the required tests.
The sealing devices currently in use operate on the principle of heat-sealing. The device typically includes a sealing head with heatable jaws for compressing the tubing. The tubing is captured within a slot between the jaws, which compress the wall of the tubing, melts and fuses it.
There are many commercially available sealing devices. One such sealing device is the Hematron II available from Baxter Healthcare Corporation of Deerfield, Ill. The Hematron II is a portable, dielectric sealing device that includes a single sealing head. Multiple tubing segments can be provided by manually advancing the tube through the sealing head and sealing the tubing at the desired locations.
Another manufacturer of sealing devices is Starstedt of Newton, N.C. which provides a stationary device (as contrasted to a hand-held device of the type described below). Several modules of this device, each having a single sealing head, can be placed in a series to provide multiple (up to 6) seals in the tubing.
More recently, hand-held sealing devices have been introduced. Examples of such hand-held devices include the Auto-Seal, Handy-Seal and the Hematron III, all available from Baxter Healthcare Corporation. Other hand-held and/or stationary devices are available from other suppliers/manufacturers.
Although the devices currently available have generally worked satisfactorily, further improvements in the field of sealing blood tubing are desirable. For example, the sealing devices described above require either manual location of the tubing in the sealing head, manual movement or advancement of the tubing between the sealing heads or the combination of multiple sealing heads (which require greater energy, resulting in increased cost of the device).
Thus, it would be desirable to provide a sealing device that limits the amount of manual involvement and quickly provides the required number of tubing segments. It would also be desirable to provide a low-cost, energy efficient apparatus.